Drndić Lab

Research: Nanoelectronics, assembly and manipulation

We are applying the unique capabilities of our recently developed sub-nanometer precision transmission electron beam ablation lithography (TEBAL) to demonstrate that the precise integration of solid-state nanopores with nanoelectrodes, nanochannels and microfluidics will address key obstacles that must be overcome to achieve nanopore-based low-cost high-speed single molecule analysis of DNA and proteins.

Graphene, a two-dimensional carbon crystal, has been the focus of intense
research since techniques were developed to extract it from graphite in the
form of multi-layers and single layers. Graphene-based devices measured on
substrates have revealed an impressive set of exotic electronic and optical
properties with promising applications.We have recently investigated the
possibility of cutting graphene sheets with electron beams and further sculpting them
into arbitrary designs that may prove useful in graphene-based electronic and
mechanical applications.

We study biomolecule (DNA) translocations through nanopores created in graphene membranes. Devices consist of thin graphene membranes with electron-beam sculpted nanoporesa few nanometers in diameter. Due to the thin nature of the graphene membranes, larger blocked currents are measured than for traditional solid-state nanopores. Unlike traditional solid-state nanopore materials that are insulating, graphene is an excellent electrical conductor. Use of graphene as a membrane material opens the door to a new class of nanopore devices in which electronic sensing and control is performed directly at the pore.

Under continuous illumination, semiconductor nanocrystals have been observed to emit light intermittently.
This light intermittency is often called "blinking" and exhibits particular statistics.

We study nanocrystal blinking and in particular the effects of particle geometry and its environment on fluorescence
properties. Recently, we studied the blinking properties of single CdSe core and core/shell nanorods.

Nanoscale electronic devices are fabricated and characterized using electron-beam lithography and transmission
electron microscopy. Recently, we demonstrated that transmission electron beams can be used to nanosculpt thin
metal films to make integrated devices with sub-10 nm features..